// This Source Code is in the Public Domain per: http://unlicense.org
package org.litesoft.render;

public class ChildAdjustStruct
{
    private int mIndex;
    protected ChildAdjustStruct mPrev, mNext;
    private int mMaxShrinkAllowed = 0;
    private int mAdjustBy = 0;

    public ChildAdjustStruct( int pIndex, int pMaxShrinkAllowed )
    {
        mIndex = pIndex;
        mPrev = mNext = this;
        mMaxShrinkAllowed = pMaxShrinkAllowed;
    }

    public int getIndex()
    {
        return mIndex;
    }

    public int getMaxShrinkAllowed()
    {
        return mMaxShrinkAllowed;
    }

    public int getAdjustBy()
    {
        return mAdjustBy;
    }

    public void insertBefore( ChildAdjustStruct pChild )
    {
        ChildAdjustStruct zPrev = pChild.mPrev;
        pChild.mPrev = zPrev.mNext = this;
        this.mNext = pChild;
        this.mPrev = zPrev;
    }

    public void unlink()
    {
        ChildAdjustStruct zNext = mNext;
        ChildAdjustStruct zPrev = mPrev;
        zNext.mPrev = zPrev;
        zPrev.mNext = zNext;
        clearLinks();
    }

    public void clearLinks()
    {
        mPrev = mNext = null;
    }

    public int incAdjustBy()
    {
        mAdjustBy++;
        return 1;
    }

    public int incAdjustBy( int pBy )
    {
        mAdjustBy += pBy;
        return pBy;
    }

    public int decAdjustBy()
    {
        if ( mMaxShrinkAllowed > 0 )
        {
            mMaxShrinkAllowed--;
            mAdjustBy--;
            return 1;
        }
        return 0;
    }

    public int decAdjustBy( int pBy )
    {
        if ( pBy > mMaxShrinkAllowed )
        {
            pBy = mMaxShrinkAllowed;
        }
        mMaxShrinkAllowed -= pBy;
        mAdjustBy -= pBy;
        return pBy;
    }

    public String toString()
    {
        return mIndex + " x " + mAdjustBy;
    }
}